M3 Serrated Lock Washers are manufactured to DIN 6798 with a coarse thread pitch of 0.5 mm. This page lists the controlling dimensions for the M3 size — head geometry, width across flats, matching spanner size — together with the clearance hole, tapping drill and tightening torque used at assembly.
M3 Dimensional Row (DIN 6798)
| For size | Inner diameter d1 (mm) | Outer diameter d2 (mm) | Thickness h (mm) | Type | Reference standard |
|---|---|---|---|---|---|
| M3 | 3.2 | 6.0 | 0.5 | Internal-tooth type A | DIN 6798 A/J |
Spanner & Drive for M3 Serrated Lock Washers
Drive geometry for M3 Serrated Lock Washers is given by the row above; match the tool to the listed values.
Common Applications for M3 Serrated Lock Washers
M3 Serrated Lock Washers are commonly specified for small electronics hardware and precision assemblies.
Mating Parts for M3
A M3 flat washer pairs with a M3 bolt/screw and matching M3 nut.
When to Step Up or Down from M3
When the joint preload approaches the proof load of M3 class 8.8, step up to M4 class 8.8 (or move to M3 class 10.9). When the joint is over-specified, M2 often saves weight and cost without losing the safety margin.

